Refrigeration apparatuses which perform refrigeration cycles are known in the prior art. Such a type of refrigeration apparatus has been used widely as an air conditioner for providing room cooling/heating and a cooling machine such as a refrigerator, freezer or showcase for the storage of foods. Some refrigeration apparatuses provide both room cooling and refrigerator's storage space cooling (for example, see Japanese Patent Application Kokai Publication No. 2002-349980). This type of refrigeration apparatus is generally installed in convenience stores.
With reference to FIG. 11 showing a refrigerant circuit (100) of the above-described refrigeration apparatus, discharge pipes of two compressors (101, 102) join and their junction is linked to a single high-pressure gas pipe (103). The high-pressure gas pipe (103) is linked to one end of an outdoor heat exchanger (104). The other end of the outdoor heat exchanger (104) is branch-connected, through a liquid pipe (107), to one end of an air-conditioning heat exchanger (105) for room air-conditioning and to one end of a cooling heat exchanger (106) for refrigerator's storage space cooling. Branch pipes (108, 109) of the liquid pipe are provided with expansion valves (110, 111), respectively. And, the other end of the air-conditioning heat exchanger (105) is connected, through a first low-pressure gas pipe (112), to the suction side of the first compressor (101). The other end of the cooling heat exchanger (106) is connected, through a second low-pressure gas pile (113), to the suction side of the second compressor (102). By virtue of the above-described arrangement, the temperature at which refrigerant evaporates in the air-conditioning heat exchanger (105) differs from the temperature at which refrigerant evaporates in the cooling heat exchanger (106).
Problems that Invention Intends to Solve
In the above-described conventional refrigeration apparatus, however, each refrigerant circulating route requires a respective compressor, in other words the provision of the compressors (101, 102) is required. Consequently, the installation of the compressors (101, 102) requires a large space. Another problem is that the provision of the two compressors (101, 102) increases costs in comparison with the provision of a single compressor.
With the above-described problems in mind, the present invention was made. Accordingly, an object of the present invention is to accomplish installation space reduction and cost reduction by enabling a single compressor to activate a refrigeration apparatus provided with a refrigerant circuit having a plurality of refrigerant circulating routes and capable of operation in a mode where the plurality of refrigerant circulating routes differ in refrigerant evaporation temperature and/or refrigerant condensation temperature.